The present invention is generally directed to a device and method for measuring the inside diameter of a body lumen and, more particularly, of air passageways. The present invention is more particularly directed toward measuring an inside diameter of an air passageway by transorally inserting a balloon having a known volume-to-diameter relationship in the air passageway, expanding the balloon with a volume of fluid to a known transverse diameter, and determining that the transverse diameter is adjacent to opposing portions of an interior wall of the air passageway.
Several emerging technologies employ devices placed in the air passageways to diagnose and treat conditions of the lung, conditions of organs and body structures that are in proximity to the lungs, and conditions that are systemic. For example, a treatment for Chronic Obstructive Pulmonary Disease (COPD) involves placing obstructing devices in selected air passageways to collapse lung portions distal of the obstructing devices. The devices are typically placed in air passageways between approximately 4 and 10 mm in diameter.
The performance of intra-bronchial devices may be enhanced by sizing the device to fit the air passageway. However, no method or device presently exists for determining the inside diameter of an air passageway. There is a need in the art for quickly and economically measuring the inside diameter of an air passageway to assist in selecting the size of an obstructing device.
In view of the foregoing, there is a need in the art for a new and improved apparatus and method for measuring the inside diameter of air passageways.